This invention relates to an apparatus for terminating a plurality of insulated conductors by engaging and pressing such conductors into respective insulation-piercing contact portions of an electrical connector, and more particularly to a more simplified, yet reliable, conductor termination apparatus that includes structure for reducing and more efficiently distributing the operating forces necessary to achieve satisfactory conductor insertion and termination into an electrical connector.
Prior art termination tools generally include a frame or base structure, which carries a support assembly for an electrical connector, and a pair of oppositely disposed, rotatable insertion arms, each of which are designed to carry multi-blade conductor insertion tools that are used to engage and press free-ended insulated conductors into respective insulation-piercing contact portions of an electrical connector carried by the support structure. The operating force required to accomplish satisfactory conductor termination in such termination tools is generally quite high, and is most frequently applied, for example, by means of separate handles which are individually attached to each of the insertion arms, swing in a substantially horizontal plane, and engage and cam about a fulcrum means carried by the frame of the termination tool. As the handles, and therefore the insertion arms themselves, are brought together during operation of the termination apparatus, the handles first engage and then cam about the fulcrum means carried by the frame, and in this way cause the force applied to the handles by a tool operator to be rapidly translated into insertion and termination forces at the insertion arms.
Although this manner of applying operating force from a termination tool operator to the insertion arms of the tool has proved satisfactory in most applications, some operators have experienced difficulties in applying sufficient force to the oppositely disposed handles to effect termination. This has resulted in large part, because the handles, like the insertion arms, are rotatable in a substantially horizontal plane, and thus require an operator to use his hands, arms and shoulders in an unnatural scissorslike motion to apply operating forces sufficient to cause termination. In addition, the handle structures of such prior art termination tools are permanently fixed in relatively awkward positions for efficient application of operating forces and cannot be adjusted or moved to more advantageous positions to suit the particular needs of a particular operator for any given termination application.
It has also been found to be desirable in the operation of prior art termination tools to cause a slight but continuous downward pressure to be applied to the insertion arms of the termination tool during the termination operation to insure, among other things, that relatively close contact is maintained between the lower edge of multi-blade insertion tools, carried by the insertion arms, and the upper cutting edge of the electrical connector support assembly. In order to accomplish this desired application of downward pressure on the insertion arms, relatively complex spring-loaded assemblies, which are carried by the frame, are provided, in some instances, to exert the required downward pressure on the insertion arms, while, in other instances, the downward pressure is created by the combination of such spring mechanisms and a toggle-cam assembly, or by the engagement of a camming surface present on the insertion arms and a conical pin carried by the frame. In each instance, however, the structure used to achieve the required downward pressure on the insertion arms in the prior art termination tools undesirably adds a measure of cost and additional complexity to the termination tool.
As a consequence of these and various other difficulties which have been experienced with various prior art termination tools, a need has developed for a more simplified, yet reliable, termination apparatus that more readily permits the application of operating forces adequate to effect satisfactory conductor insertion and termination in an electrical connector, while at the same time, permitting the application of sufficient downward pressure on the insertion arms, without the use of complex components, to insure close contact during termination between the multi-blade insertion tools carried by the arms and the support assembly for the electrical connector.